(mozilla-projects-nss-reference-fc-encryptupdate)=

# FC_EncryptUpdate

## [Name](#name)

:::{container}
FC_EncryptUpdate - encrypt a block of a multi-part encryption operation.
:::

## [Syntax](#syntax)

:::{container}

```{code}
CK_RV FC_EncryptUpdate(
  CK_SESSION_HANDLE hSession,
  CK_BYTE_PTR pPart,
  CK_ULONG usPartLen,
  CK_BYTE_PTR pEncryptedPart,
  CK_ULONG_PTR pusEncryptedPartLen
);
```

:::

## [Parameters](#parameters)

:::{container}
`hSession`

: [in] session handle.

`pPart`

: [in] pointer to the next block of data to be encrypted.

`usPartLen`

: [in] length of data block in bytes.

`pEncryptedPart`

: [out] pointer to location where encrypted block is to be stored.

`pusEncryptedPartaLen`

: [out] pointer the location where the number of bytes of encrypted data is to be stored.
:::

## [Description](#description)

:::{container}
`FC_EncryptUpdate` encrypts a block of data according to the attributes of the previous call to
`FC_EncryptInit`. The block may be part of a multi-part encryption operation.

A user must log into the token (to assume the NSS User role) before calling `FC_EncryptUpdate`.
:::

## [Return value](#return_value)

## [Examples](#examples)

## [See also](#see_also)

:::{container}

- {ref}`mozilla_projects_nss_reference_fc_encryptinit`,
  [NSC_EncryptUpdate](/en-US/NSC_EncryptUpdate)
:::